Loop-taker-actuating mechanism for sewing-machines.



. PATBNTBD PEB. 25, 1908.

P. DIBHL` L00P TAKER AGTUATING MEGHANISM FOR SEWING MACHINES.

APPLIUATIGN FILED (-)0T.13,.1905.

fal.

PHILIP DIEHL, OF ELIZABETH, NEW JERSEY, ASSIGNOR TO THE SINGER MANUFACTURING COMPANY, A CORPORATION OF NEW JERSEY.

LOOP-TAKER-ACTUATIN G MECHANISM FOR SEWIN G-MACHIN ES.

Specification of Letters Patent.

Patented Feb. 25, 1908.

Application filed October 13| 1905. Serial No. 282.560.

To all whom it may concern:

Be it known that I, PHILIP DIEHL, a citi- Zen of the United States, residing at Elizabeth, in the county of Union and State of New Jersey, have invented certain new and useful Improvements in Loop-Taker-Actuating Mechanism for Sewing-Machines, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention relates to an improvement in sewing machines adapted to operate at high speeds, and particularly to that class of sewing machines comprising a reciprocating needle and a rotating lock-stitch loop-taker making two revolutions to each reciprocation of the needle-bar. In such high-speed lock-stitch machines it has been customary heretofore to communicate from the main shaft, journaled in the bracket-arm, to the looptaker actuating shaft mounted beneath the bed-plate, the relative two-to-one movements either by means of a perforated belt embracing pin-wheels upon the respective shafts, or by means of properly proportioned gear-wheels connecting such looptaker actuating shaft and an intermediate lower shaft deriving its rotary movements from the main shaft through suitable means, as doublecrankand-pitman connections. The firstof these expedients has been found objectionable to a certain extent for the reason that a non-extensible metallic belt has proved unsuitable because 0f its insuicient pliability,and hence its lack of durability in standing the rapid changes of form to which it is subjected in its embrace of the pinwheels, while the non-metallic belts have been subject to stretching to such extent that its perforations have been frequently thrown out of register with the pins of the wheels between which it transmits motion, thereby causing the loop-taker to operate out of its proper time with the needle. The use of spur gearing in connecting the lower shafts is objectionable for high-speed machines on account of the noise and excessive injury resulting from the entrance and recession of the teeth of one into and out of the spaces intermediate the teeth of the other.

The present invention has for its object to provide a positive connection between the needle and the two-to-one rotary loop-taker cooperating therewith in which the contact vbeing indicated in dotted lines.

' of the intermeshing parts of the connecting members shall be constant, whereby the engagement and disengagement of such parts resulting from the use of the perforated belt and pin-wheel or the spur-gearing before mentioned may be wholly obviated.

' In the preferred form of the present invention, I make use of the trammel principle in constructing the connection between the lower intermediate and the loop-taker shafts, the intermediate shaft being provided with a disk having crossing diametrical grooves or slide-ways in each of which is fitted a slideblock receiving one of two diametrically-disposed crank-pins carried by a crank-head upon the eccentrically-arranged loop-taker shaft, the intermediate shaft receiving its positive rotary movement from the main shaft by means of a well-known form of double-crank-an d-pitman connection Inasmuch as the needle-bar which carries the needle has a positive pitman connection with a crank upon the forward end of the main shaft, it will be seen that every part of the several connecting members intermediate the needle and the loop-taker maintains its normal contact and operative relation with the interengaging part, whereby any pounding of the component members productive of noise and injury is entirely avoided and the entire train of mechanism is caused to operate smoothly and noiselessly.

The invention will be understood by reference to the annexed drawings in which,-

Figure 1 is an elevation of a sewing machine embodying my improvements, certain portions being broken away to expose the parts which would be otherwise hidden thereby. Fig.Y 2 is a view of the under side of the machine with the cap of the oil receptacle Of the trammel connection removed. Figs. 3 and 4 are face views of the grooved disk of the trammel connection and the slide-blocks in different positions therein, the crank-head Fig. 5 is a perspective representation of the two slideblocks.

The machine herein represented is of the wellknown Singer revolving-hook type disclosed in the United States patent to Phili Diehl, No. 663,808, Dec. l1, 1900, and is constructed with the usual bed-plate 1 and bracket-arm 2 in which latter is journaled the main shaft 3 having at its forward end the crank 4 whose pin is embraced by the upper end of the pitman 5 having its lower end pivotally connected with the needle-bar 6 carrying the needle 7 deriving from such connections with the main shaft one reciprocation 5 for each rotation of the latter. The main shaft is provided near its rearward end with the quartering cranks 8 each of which is ernbraced by the upper end of a pitman 9 extending downwardly through the columnar portion of the bracket-arm to embrace the quartering cranks 10 upon the rear end of the intermediate shaft 11. According to the present improvement, the shaft 11 is mounted in suitable bearings 12 upon the under side 15 of the bed-plate provided at its forward end with the fixed disk 13 having diametricallydisposed grooves or slide-ways 14 arranged at right angles. The loop-taker shaft 15 is journaled in the bearing lug 16 depending from the bed-plate and carries at itsforward end the loop-taking hook 17, which is of the single-hook class commonly employed iny multi-rotation loop-taker lock-stitch machines and which may be of the kind represented in the United States patent to Martin Hemleb, No. 741,035, dated Oct. 13, 1903, and at its rearward end the crank-head 18 having the rearwardly-projecting and diametrically opposite crank-pins 19 fitted to suitable apertures 20 in the slide-blocks 21 and 22 each fitted to its respective groove or slide-way 14 in the disk 13. The crank-pins 19 are equidistant from the axis of the actuating shaft 15, which latter is disposed above the axial line of the intermediate shaft 11 a distance equal to that of its crank-pins from its own axis, whereby the rotation of the shafts causes the slide-blocks 21 and 22 to alternately approach and recede from the center of the disk 13.

In Fig. 4 the crank-pins 19 and their slideblocks 21 and 22, respectively, are represented in their extreme upper and lower positions. When the disk 13 has made oneeighth of a turn, the crank-pins 19 have made one-quarter turn and assume a horizontal position. The `continued movement of the disk 13 through the succeeding one-eighth of a turn causes the slide-blocks 21 and22 to exchange the positions represented in Fig. 4, the loop-taker shaft 15 having received a half rotation by the quarter rotation of the intermediate shaft 11. Itis evident that the continued rotation of the disk 13 through a complete rotation will cause a double rotation of the shaft 15.

It is of great importance that the slideblocks 21 and 22 be given ample contact surface with the walls of their respective slide- 60 ways, in order that each may be accurately guided across the slide-way of the other and may avoid impact against the corners formed by the intersection of such slide-ways. In order that the blocks may be given a rec- 65 t'angular form of the requisite length, and yet avoid interference in their dierential movements to and from the point of intersection of their slide-ways, their end portions are cut away upon the adjacent faces, as represented more particularly in Fig. 5, to make the length of the reduced portion of each equal to the width of the slide-way of the other block, whereby ample clearance is afforded to enable the adjacent end-portions of the two'blocks to overlap as they approach each 75 other, as represented in Fig. 3, while the edges vof such overlapping portions are adapted to continue in contact relation with the walls of the respective slide-ways to maintain their alinement. While the notches in the end portions of the slide-blocks are represented as of rectangular form, it is evident they may, if desired, be shaped so as to present a sufficient clearance for the purpose indicated, and that, if desired, one corner only of each end portion may be partially removed for the purpose.

ln the use of sliding connections working at such high speeds as are required in mechanism of the character referred to, it is irnportant that sufficient lubricant be acquired to afford the best possible conditions of operation. To this end l have provided intermediate the bearing lugs 12 and 16 upon opposite sides of the trammel connection a cavity 23 which is closed upon the lower side by meansof a suitable cap 24 fitted closely thereto and serving as an oil cavity in which a small quantity of oil 25 may be held which latter is entered by the rim of the disk 13, which serves to diffuse the oil through the working parts and produce the desired lubrication. The casing thus afforded also serves as a housing to exclude lint and dirt so as to keep the working parts within clean and prevent their becoming clogged so as to impair the efficiency of the mechanism.

ln order to impose theleast possible labor upon the shaft 15 and its connections with the main shaft, and to insure the greatest possible uniformity of the load imposed thereon, the feed-actuating rock shaft 26 and feed-lifting rock-shaft 27 are provided with independent connections with the main shaft by means of the pitmen 28 and 29 and eccen- 115 tric and crank 30 and 31, respectively, but these parts are not material to the present invention.

From the foregoing description, it is evident that, while that represented in the ac- 120 companying drawings is a preferred form of the present improvement, t e present invention is `not limited to the precise details of construction and arrangement herein set forth.

Having thus set forth the nature of the invention, what I claim herein is,-

1. In combination, a main-shaft, a reciprocating needle, o erative connections between said main-s aft and needle whereby 130 the latter receives a single reciprocation for each rotation of the former, feeding mechanism, operative connections between the same and the main-shaft, a single-hook loop-taker adapted to cooperate with said needle in the production of stitches, a shaft parallel with the main-shaft and carrying the loop-taker mounted thereon with the plane of movement of its hook adjacent and parallel with the path of reciprocation of the needle, a third shaft parallel with but offset from the loop-taker shaft, a trammel-wheel mounted upon the end of said third shaft, a pluralarmed crank adapted to coperate with said trammel-wheel and mounted upon said looptaker shaft, whereby the speed of said looptaker shaft is accelerated beyond that of said third shaft, and an operative connection between said main-shaft and said third shaft.

2. In combination, a main-shaft, a reciprocating needle, operative connections between said main-shaft and needle whereby the latter receives a single reciprocation for each rotation of the former, feeding mechanism, operative connections between the same and the main-shaft, a single-hook loop-taker adapted to coperate with said needle in the production of stitches, a shaft parallel with the main-shaft and carrying the loop-taker mounted thereon with the plane of movement of its hook adjacent and parallel with the path of reciprocation of the needle, a third shaft parallel with but offset from the loop-taker shaft, a trammel-wheel mounted upon the end of said third shaft, a pluralarmed crank adapted to coperate with said trammel-wheel and mounted upon said looptaker shaft, whereby the speed of said looptaker shaft is accelerated beyond that of said third shaft, and an operative connection between said main-shaft and said third shaft consisting of a pair of angularly-disposed cranks correspondingly arranged upon each of said shafts and a pitman-rod connecting each crank upon one shaft with the corresponding crank upon the other shaft.

3. In a sewing-machine, the combination with the frame comprising the bed-plate and bracket-arm, of a main shaft journaled in the bracket-arm, a needle-bar carrying a needle and a positive crank-and-pitman connection between said needle-bar and the main shaft, an intermediate shaft mounted beneath the bed-plate, crank-and-pitman connections between said intermediate shaft and the main shaft, a loop-taker shaft also mounted beneath the bed-plate eccentrically in respect of said intermediate shaft and carrying at its forward end. a rotary loop-taker, a disk mounted upon the forward end of said intermediate shaft and provided with a plurality of intersecting diametrically-dis'posed grooves or slide-ways, elongated slide-blocks disposed in said grooves or slide-ways and having their ends partially cut away upon the adjacent faces to enable them to partially overlap, and a crank-head iiXed upon the rear end of said loop-taker shaft and provided with crank-pins each entering a suitable aperture in one of said slide-blocks.

4. In a sewing machine, the combination with the frame comprising the bed-plate provided with a cavity in its lower side and a removable cap for closing the bottom of the same and providing therefor a detachable oil-holding cup or reservoir, within the cap therefore and the bracket-arm secured upon said bed-plate, of a main shaft journaled in the bracket-arm, a needle-bar carrying a needle and a positive crank-and-pitman connection between said needle-bar and the main shaft, an intermediate shaft mounted beneath the bed-plate, crank-and-pitman connections between said intermediate shaft and the main shaft, a loop-taker shaft also mounted beneath the bed-plate eccentrically in respect of said intermediate shaft and carrying at its forward end a rotary loop-taker, a disk mounted upon the forward end of said intermediate shaft within said cavity of the bed-plate and within the cap therefor and provided with a plurality of intersecting diametrically-disposed grooves, and a crankhead iixed upon the rear end of said looptaker shaft also disposed within said cavity of the bed-plate and provided with a plurality of crank-pins each entering one of said intersecting grooves. Y

In testimony whereof, I have signed my name to this specification, in the presence of two subscribing witnesses.

H. A. KORNEMANN, JOSEPH F. JAQUITH. 

